High-temperature conductivity in chemical bath deposited copper selenide thin films

This paper reports high-temperature (305-523 K) electrical studies of chemical bath deposited copper (I) selenide (Cu _2-xSe) and copper (II) selenide (Cu ₃Se ₂) thin films. Cu _2-xSe and Cu ₃Se ₂ have been prepared on glass substrates from the same chemical bath at room temperature by controlling the pH. From X-ray diffraction (XRD) profiles, it has been found that Cu _2-xSe and Cu ₃Se ₂ have cubic and tetragonal structures, respectively. The composition of the chemical constituent in the films has been confirmed from XRD data and energy-dispersive X-ray analysis (EDAX). It has been found that both phases of copper selenide thin films have thermally activated conduction in the high-temperature range. In this paper we also report the variation of electrical parameters with film thickness and the applied voltage.